A fraternity consisting of 20 sophomores, 20 juniors, and 20 seniors is about to elect its next

Question:

A fraternity consisting of 20 sophomores, 20 juniors, and 20 seniors is about to elect its next president. Arnold, Bo, and Chuck are the three candidates. Members of each class have the ranking schemes given in the table:

The tradition in the fraternity is to pit two candidates against each other and then pit the winner of that contest against the third candidate. If you were a sophomore, whom would you pair off in the preliminary round? If you were asenior?